This invention relates to a wheel type weft straightener which is suitable to be attached to various cloth treating machines such as those for dyeing, printing and finishing of natural and synthetic fiber cloths including woven and knitted fabrics, and straightens the skewed or bowed weft of a travelling cloth.
European Patent No. 0136115 and U.S. Pat. No. 4,932,106 disclose a weft straightener comprising a machine frame; a pair of wheels for holding each selvedge of a cloth on the outer periphery of each wheel; wheel supporting means for keeping each wheel rotatably, inclinably and widthwise-movably on each side of the machine frame; wheel inclination adjusting means for adjusting each wheel to a desired inclination angle; and wheel position adjusting means for adjusting each wheel to a desired position in the widthwise direction; whereby the difference of rotation speed of both wheels is made while the cloth is travelling with its each selvedge held on the outer periphery of each wheel so that the skewed or bowed weft of the cloth may be straightened.
However, the conventional wheel type weft straightener above mentioned had the problems that, when either selvedge of the cloth falls off from the outer periphery of the wheel due to causes such as partial unevenness of the selvedge, there is the possibility that the cloth being downwardly suspended gets partly caught in the inner members of the weft straightener or twines round the rotary members of the weft straightener, and operators cannot but interrupt the operation of the weft straightener to stop the travel of the cloth and treat the cloth to be restored to the former state by hand so that the selvedge of the cloth may be held again on the outer periphery of the wheel, so that it is difficult to efficiently restore the cloth by hand to the former state because the cloth has been downwardly suspended.
Furthermore, the conventional weft straightener, wherein each wheel which is free to rotate is provided and rotated, interlocking with each selvedge of the travelling cloth and stretching the cloth in the widthwise direction, had the drawbacks that they cannot be easily applied for those cloths such as knitted fabrics which are very stretchable and transformable, though they are preferably applied for those cloths such as woven fabrics which are not stretchable under usual tension.
Accordingly an object of the present invention is to provide a wheel type weft straightener wherein, when either selvedge of the cloth falls off from the outer periphery of the wheel, the/cloth is prevented from being downwardly suspended and the selvedge having fallen off comes to be held again on the outer periphery of the wheels as in the former state without the interruption of the operation of the weft straightener.
Furthermore, it is another object of the invention to provide a wheel type weft straightener which is preferably applied for not only the woven fabrics but also the knitted fabrics.
Other and further objects, features and advantages of the invention will become more apparent from the following description.